Perinatal risk factors for childhood testicular germ-cell cancer: a Nordic population-based study

Introduction: In contrast to research in adults, there have been limited studies on testicular germ-cell cancer among boys aged <15 years. The aim of the study was to investigate the association between perinatal characteristics and childhood testicular germ-cell cancer.

Methods: We identified 152 patients with childhood germ-cell cancer among boys (<15 years) born in Norway, Sweden, Finland and Denmark between 1967 and 2006 using the cancer and medical birth registries. For each case we sampled 10 population controls matched on year and country of birth. We used conditional logistic regression analysis to estimate odds ratios for cancer risk.

Results: There was a weak, positive association between high (≥4000 g) birth weight and childhood testicular germ-cell cancer (adjusted OR=1.25; 95% CI: 0.83-1.90) compared with normal birth weight, and a correspondingly elevated risk for low birth weight (adjusted OR=1.41; 95% CI: 0.43-4.56). For Ponderal Index (PI) there was an increased risk for low and high values compared to those in the middle category (adjusted OR=1.64; 95% CI: 1.03-2.62 and 1.67; 95% CI: 0.93-2.99), respectively. There was no association between birth length and childhood testicular germ-cell cancer. The adjusted OR for testicular cancer among first born was 1.40; 95% CI: 0.96-2.05. Greater maternal age and less maternal education appeared to increase the risk, but the estimates were not statistically significant.

Conclusion: We found a U-shaped association between fetal growth, measured as the PI, and childhood testicular germ-cell cancer. Our findings support the notion that abnormal fetal growth rate confers a risk in pediatric testicular cancer [corrected].